Ellipsograph



July 26, 1949.. N. RABINOWITZ 2,477,203

I ELLIPSOGRAPH Filed May 8, 1945 2 Sheets-Sheet 1 n mu m mum lllllnyj July 26, B949. N. RABINOWITZ ELLIPS OGRAPH 2 Sheets-She et 2 1 Filed May 8, 1945 Patented July 26, 1949 5 m @FFIQE "2,477,208 lem neian" 'Nalthan Rabinowitz, Bmum mnw. v mimenew 1945,.eeiitmegee e This invention relates to drawing instruments, and more particularly to thos of theeharaeter empleyedtfor drawing oval oriellipticaliigneest While efforts have been lnade in .the past J10 produce satisfactory .instrumeintseof this character lay-means of which elliptical fi ulzes enuld be drawn, wholly satisfactory results have not been obtained marticularly {or the production 40f relatively small andaecnrate ellipses.

The present ,invention "therefore inontemplatesthe,proyisionof a device .ofthiseehalranter which can he precision-made which ,will draw .oval qr elliptical ifigures in tvarioussizes, within its range, with speed and ,precisiqn and which .will nonstitute a dependable and iaceurate drafting ;.in.- strument. e V

Referring to the accompanying drawings, in which an illustrative; embodiment inf the invention is shown, Fig. ,-1 is a pl-anyiew 131121143 improved drawing instrument, vieonstfrllcted in ac eordance with the inventinn; eliig. 2 his 110th zontal sectional vieweon the ;.line rll-e2 of Fig- 54, looking in thedirection-ioithe arrows; Fig-.3 is a diagram -l'11ustraiting the principle tot pexation of the device; .Fig. 51.- is a vertical sectional .lliew through the device; .Eig. 5 is .a .vertieahwetional View .taken at right. angle to l that let a4; ,eFig. 6 anelevational view-,nfmne .end afithe ins rument, and Fig. (7-is aview -of-thetqppositfi end- Theedevice includes a housing J shown testbeing relatively fiatsothat itimay hegplaced upon a surface upon whi'qh-the zfignreisttobe drawn, (and substantiall sguane .in .shape. housingmay, of course, be-ofiother shapeiii desired. In the form showm-it .is provided with the four vertically-disposed sidewallsiznii diand 5. .The topplatefi of .the ihousingtis ,prpvided witha circuleranertune 1 to discl se amtatable disks. mounted below it, said .disk heing ratatively supported 21113011 an annular shell member =91 ledge 9 located within ntheihousihg nd provided with the .eentral .apertune 1 a-thm lg which 4 .1 under. faceiof the .diskJ) :is ieiillused. Anrannzular spacer ll islocetedadiacentitheiperipheraliedge of theidisk ,8 i to. accuratelyi-centertthe disk in the housing, ermitting itsmannal ;r0ta.tion- .as therein described, but -maintaining lit IfIQm zlateral displacement.

The "entire peripheral oedgetof the edisl; 8 his toothed as indicated at l2, and. thees-ide .-wal1 .5 of thehonsineis slottednas indicated: at 3 I 3 :(Eig. 6) to permit .of ..-the prQtrlwiQn ef e ipertlen Qfif the toothediedee l 2 -.0fv-the@- dish-8 east elearldeseep in'Figs. 1, 2 and 6. Rotatively mounted ion s '8 Cl s- (ct 3 3-30) musin a pinion 45 n meshed engagement.

spindle J4 on theinutside.ofimeewalltfi at the a with .the 'itoethedi d l2 ..o.f vth .disk- :A isenohd pinion L6, .rotativ .911 aespindl-e ,IJ, m shes w th the million 15 and l else meshes with th e J'QQ-fihfill edge -L8 nfanisk L9 .loea edwlthin th h nting I andibeletvitheld skiil; themsk. .13 .being similar insizeand QenstructionJ19.itheas id'llhpertdislsj.

Through the arrangement \ebnve describ d, it will be noted that there is rotatively ,mo ited ithin .the housing J, .a air .nf, sp /ted, simila toothed-edge disks 8 and I9, andthatmthese v are ,eaused -..to.retate iteg ther, -at the same spee andin thesamedireetion vwhenione .Q them. -9 hat shownjat i8, is manually .rntated, .by m ans of "th interm'esh .nf .the .disks with the mep ere ating pinions J5 and L5. "The .lQWQr ad fik J9 retativelysunn r ednmntheinturnediflan fli 01f an .annnlus .2 I seeured in the ,lnwer ipnrtion of the hunting 4! and fa pn'rt on .ef th tonthed edge 1'8 .o'f theJnwen disk L9 ,prot nd s elite? the side wall};of thehousin rtnreaehan m ith pinion [6, as icleerlmeen inhig, .6. .If desired, he pnrtions ,of l'theidislss ;8 en A9 whi h PIQJQ fmmithehousineaswell as-i-thepin nns l5 and I6 an eoyered endithus pmtectedbye suitable eoverimemberenot shown fer simp ici yiiniillustration 'flfhejoweridisk ;.l-,9.is .eenfinedhe weenithe lipnerifa e "of the flange ill anditheibottqm of ,a ring :22 secu ed to the .walls of th eas ng, said ring 1221forming .a ledeeqrshelf iflq Ya sl d-able, slotted ibar e23 pmvided tor most i of its len th with a'.loneitudinallyeextendingislet 2.4- .zFn mtli in'th JQWGLQiSK L9 is .aireiiiallmex en ineelnt 25in which a setting-pin 26vis adinstable. ,fiaid pin -26 .is amv ilesi wi h th tfineer pieee 1,21 efm which a' thread dshank '2 extends, ssaid shank adiustaloly ei 1 e= g ing.n nut-Heist tha wh n the sfitting pin is lpnsened in the nut (19 th min amiithe-mitican hesliclilal n ini-tl eislbm Estes desired xtent 'eec rding tte .aesca le inn vides @1 the iaeenfthe idisliuand tnenltig tened neeny pesitien inf adjustment iin the slot. It wil inserted-thatth esett ne ninehfi:i eamyidedwwith an extnennty eretip wenterinslmto theisletiae n uthe. sliclahle ebar 1:23, this tip er aexteemity 310 oftthe nimzfiirid he ini-thecsl trzfl hi theebarild.

esiseeniinl-liigh i, I

w Jim 3 lise enfined shetweenctiievring: 22 land :a shelf eerlledge @31L3fi1h islidably :meuntedi'nn imp Gi t-1 m led eiil [is aasecend elottembarssz extendingeatargghtuai gle ntnaaifldeaicrnss thentopeofethe finst sslQ tnd libar '24. ilhe seeen'd Hoar though tudi liyesleted aseetzdhandnmovahly' necetvad'in thw ot 333stetheatmtmextremityeidwf a setting pin 35 similar in construction to that shown at 26, in that it has a finger-piece 36 and threaded shank 31, the latter engaging a nut 38 for holding the pin in any set position of adjustment in a radially-extending slot 33 in the top disk 8. Rising from the top face of the disk 8 is a yokeshaped operating member 40 having a fingerpiece 4| located directly over the center of the disk 8, and which is employed to manually rotate the two disks to operate the instrument.-

The beam 42 constituting the translating device which draws the oval or elliptical figures, is provided at one end with a suitable sleeve-like holder 43 in which a pencil, pen, stylus or other suitable inscribing device, may be securely held. The opposite end of the beam 42 is provided with a vertically-disposed pin 44 having one end-portion entering into the slot 24 in the bar 23, and its other end entering into the slot 33 of the slid able bar 32, as clearly seen in Figs. 4 and 5. Formed in the beam 42 is a longitudinal slot 45 into which extends a protuberance 46 secured to or formed on and arising from the top of the slidable bar'23 adjacent to one of its ends, as seen in Fig. 4. The end wall 4 of the housing is formed with an elongated slot 41, seen in Fig. 7, through which the beam 42 protrudes, and in which the beam is movable when drawing an oval or elliptical figure.

Briefly, the manner in which the device operates is as follows:

The mode of operation of a device of this character is based on the theory that when a radius cuts the circumferences of two concentric circles, said circles being indicated at a and b in Fig. 3, at the points c and d, then the horizontal ordinate ef, cutting the circle b at the point d, and the vertical ordinate g-h, cutting the circle a at the point 0, meet the point i on the line of the ellipse. In setting the instrument to draw an ellipse of a given size, the width of the ellipse to be drawn is determined by the setting of the upper pin 35 in the slot 39 of the upper disk 8. As will be noted in Fig. 1, the upper face of the disk 8 is scaled or calibratedat 48 along the edge of the slot 39, and the pin 35 is provided with a pointer 49 for use in conjunction with the scale to enable the desired setting to be secured, and thus the width of the figure to be drawn, to be secured. The length of the elliptical figure is determined by the setting of the lower pin 26 in the slot 25 in the lower disk l3, said pin 26 also having a pointer for co-operation with a scale of calibrations on the lower disk 19 situated adjacent to the slot 25 therein.

The settings of the pins 26 and 35 thus correspond to the points and d in the diagram of Fig. 3, and the resultant positioning of the pin 44 of the beam 42 in the two slots 33 and 24'as a result of the shift of the bars 23 and 32, corresponds to the oval-defining point i of the diagram. As the top disk 8 is rotated by manipulation of the finger-piece 4| of the yoke 40, it will also rotate the lower disk IS in the same direction and at the same speed. The setting-pins 26 and 35 will slide the bars 23 and 32 to the extent determined by the positions of the setting-pins in the respective slots 39 and 25, causing the pin 44 at the inner end of the beam 42 to be moved through an elliptical path, and the marking device 44a carried at the opposite end of the beam 42 to translate the movement of the inner end of the beam on a sheet of paper or other suitable surface on which the instrument is rested. The width and length of the elliptical figure so produced, will be determined by the settings of the pins 35 and 26 as heretofore explained, and since said settings are easily and accurately secured and maintained by loosening, shifting and then tightening the pins, the results secured from the instrument, from relatively small elliptical figures to increased sizes within the range of the instrument, are precise and accurate, yet can be drawn speedily and with confidence.

It will be understood that various modifications may be readily made in the structure without departing from the spirit of the invention,

since the proportions and arrangements of the parts illustrated have been materially exaggerated in order to clearly disclose the mode of operation of the device. Hence, while I have described one embodiment of the invention, it is obvious that the same is not to be restricted thereto, but is broad enough to cover all structures coming Within the scope of the annexed claims;

What I'claim is:

1. In an instrument for drawing elliptical figures, a pair of rotatable disks and means by which said disks can be simultaneously rotated in the same direction and at the same speed, each disk having a radially-extending slot, a pin adjustable along each slot, a pair of crossed bars between the disks, said bars being shiftable transversely of their length and at right angles to one another, each bar having an elongated slot, one of the pins entering the slot in one bar and the other pin entering the slot in the other bar, a beam having a projection at one end entering and movable in the slots in both bars, and a reproducing element at the end of the beam opposite to that on which the projection is situated.

2. In an instrument for drawing elliptical figures, a housing in which a pair of spaced parallel disks is rotatably mounted, means for coupling said disks to cause the same to be both rotatably moved at the same speed and in the same direction when rotative manual movement is applied to one of them, a pair of slidable bars in the housing between the parallel disks, one of said bars being slidable in a direction at right angles to the direction of sliding movement of the second bar, both bars being slidable transversely of their length, the disks each having a radial slot, a pin 50 adjustable along each slot, each pin having an element slidably engaging one of the bars, a translating device in the form of a beam carried by one of the bars and slidable longitudinally of the same, said beam being provided with a proje-ction adjacent to one of its ends entering into slidable engagement with both bars.

3. In an instrument for drawing elliptical figures, a pair of parallel disks rotated at the same speed and in the same direction, a pair of crossed slotted bars between the disks, said bars being mounted for sliding movement transversely of their length and relative to one another and at right angles to one'another, each disk having a pin adjustable radially of the disk, the pin on one disk entering the slot in one of the bars and the pin on the other disk entering the slot in the other bar, a beam having a free end carrying an inscribing device and having its other end provided with parts in movable engagement with the slots in both bars.

4. In an instrument for drawing elliptical figures as provided for in claim 3, wherein means is provided by which the beam is slidable in relation to both bars.

75 5. In an instrument for drawing ellipses, a

housing of substantially-square shape and open at its top and bottom, a pair of spaced, horizontally-disposed gears within said housing, a face of the upper gear being exposed in the open top of the housing, a face of the lower gear being exposed in the open bottom of the housing, a slotted bar located above the lower gear and movable transversely of its length with a side-toside slidin movement within the confines of the housing, the lower gear having a radially-extending slot, a pin passing through the slot in the lower gear and provided with means for fixedly positioning it at any selected point therein, said pin having a terminal portion riding in the slot in the bar, a beam carried over the bar and having a projection entering the slot in the bar, said beam having a portion projecting laterally of the casing and carrying an inscribing element, a second slotted bar mounted below the upper gear and above the first bar and movable transversely of its length, the second bar having a slot disposed at right angles to that in the first bar, a radially adjustable pin in the upper gear havin a terminal portion entering the slot in the second bar, the projection on the beam also entering the slot in the second bar.

6. In an instrument for drawing ellipses as provided for in claim 5, wherein the gears have toothed portions protruding outside of the housing, gearing disposed between said gears and serving to drive the gears at the same speed and in the same direction when one of the gears is manually rotated, and a centrally-positioned operating handle arising from one of the gears.

'7. In an instrument for drawing elliptical figures, a housing, a pair of simultaneously rotated members therein, each of said members being radially slotted, a pair of slotted bars slidable transversely of their length and relatively to the rotatable members, one of said members being slidable in a direction substantially at right anlges to the direction of slidable movement of the second bar, a, setting member adjustable along the slot of one of the rotatable members, said setting member having a projection entering the slot in one of the bars, a similar setting member adjustable along the slot in the second rotatable memher and having a rojection entering the slot in the second bar, and a beam longitudinally adjustable along the slot in one of the bars, said beam having a projection at one end entering the slots in both bars, and a reproducing element at the other end of the beam.

8. In an instrument for drawing elliptical fig ures, a pair of superimposed disks located in parallel planes, gearing means for causing said disks to rotate together when one of them is manually rotated, a pair of horizontally-mounted slidable members extending for the full diameter of the disks, each of said members being slidable transversely of its length and in a direction at right angles to the direction of sliding movement of the other member, each disk having a projection adjustable transversely across it for selective location at any desired point in the radius of the disk, each projection being in slidable engagement with one of the members in a manner to permit the projection to move longitudinally of the member which it engages upon rotation of the disks, and a beam having an end slidably connected to both of said members in a manner to cause the movements of said members to control the movements of the beam, said beam having an inscribing device that is carried through a path of movement similar to that of the end of the beam which is in slidable engagement with said members when the two disks are rotated.

NATHAN RABINOWITZ.

REFERENCES CITED The following referenices are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 296,100 Abbott Apr. 1, 1884 FOREIGN PATENTS Number Country Date 113 Great Britain Jan. 2, 1894 636,233 Germany Oct. 5, 1936 

